The present invention relates to a microscissors device for use in microvascular end-to-side anastomosis, and to an end-to-side vascular anastomotic repair technique.
Normal blood flow in a vessel (arteries and veins) is smooth and laminar, with blood flow determined by the pressure differential across the vessel and the resistance to flow offered by the vessel. As the diameter of a vessel decreases, there is a rise in the resistance to the flow of blood. Other factors affecting blood flow include the oscillatory stress or pulsating pressure in arteries, and vessel branching or bifurcation. The latter factor, vessel branching or bifurcation, is very important in microvascular surgery of reconstructed vessels.
Microvascular reconstruction is a reliable procedure when both donor and recipient vessels are normal; however, the success of reconstruction procedures in arterial and venous microsurgery largely depends on the union or anastomotic patency of the reconstructed vessels. If there is any obstruction in the reconstructed vessels, vascular thrombosis or clotting may result.
Generally, two procedures are employed in microvascular surgery of reconstructed vessels. One conventional technique is an end-to-end (ETE) anastomosis where the ends of the vessels are sutured together. The other technique is end-to-side (ETS) anastomosis. The present invention relates to the latter technique.
Historically, surgeons performing an end-to-side (ETS) anastomosis have made two angular and intersecting incisions forming a generally v-shaped excision in the recipient vessel at the planned donor implantation site. In order to make these incisions as close as possible to the approximate size and dimension of the donor vessel, the surgeon is required to make multiple manipulations of the vessel along with a final trimming maneuver.
There have been several attempts by experienced microsurgeons to bypass this method of recipient vessel preparation. These have included placing a suture through the vessel wall and using the tails of these sutures as a traction device, causing a "tenting" of the arterial or vein wall. This "tented" region is then excised with microscissors. While the "tented" region affords the surgeon a better opportunity and greater vision to make the desired excision, surgeons still have little control over the size and shape of the excision.
As has been explained above, any obstruction to normal blood flow in vessels is undesirable. Unfortunately, the aforementioned end-to-side anastomotic repair techniques may result in a vessel obstruction, due to non-uniformities in forming the excision at the desired location. Suturing of the donor and recipient vessel in the excised area also does not alleviate the damage already done by a non-uniform and unreliable excision made in the recipient vessel wall.